Good news perhaps for anyone planning a summer holiday in Europe: A new study has found that the continent has had the warmest summers since the days of the Roman empire. Since 1986, average summer temperatures have been about 1.3 degrees Celsius (34.3 degrees Fahrenheit) hotter than they were 2,000 years ago, while heat waves have been occurring more often and lasting longer.
Friday’s study, published by the Environmental Research Letters Journal, was compiled by 40 prominent academics using both modern climate measuring methods and historical documentation. Data from the years preceding 755 was predominantly calculated by analyzing the tree rings and the density of three pine species found in Austria, Sweden and Finland. These trees grow in the summer and lie dormant in the winter.
But, though the idea of hotter summers may appeal, the report has a serious message. Speaking to The Guardian, Jürg Luterbacher, the report’s coordinator, called the level of warming “unprecedented.” He added that it was his view that human activities were the cause: “It is exceptionally high and cannot be explained by natural variability, tropical volcanoes or solar changes. It is because of anthropogenic climate change.”
The report found that summers were warmer between Roman times and the third century. They then started to cool until the 7th century, before picking up again. From the 14th to the 19th centuries, Europe was plunged into a mini ice age, until the 20th century when the effects of climate change due to industrialization began warming the continent again.